缩硫醛

For the synthesis of NHC precursors, there are also several routes: condensation of glyoxal, amines and paraformaldehyde; alkylation of imidazole or monosubstituted imidazole with alkyl halide; annulation of ortho esters and 1,2-diamines; ring closure of hydrazines or amides with acetic anhydride; reduction of thiones with Na/K in THF.

关于N-杂环卡宾前体的合成途径主要有：乙二醛、伯胺和多聚甲醛的缩合反应；卤代烷与咪唑及其取代咪唑的烷基化反应；原甲酸酯与1，2-二胺的成环反应；肼或酰胺与酸酐的环化反应；用Na/K对环硫脲化合物的还原反应。

In the part two, we reported the classical Knoevenagel condensation between aromatic aldehydes and acyclic active methylene compounds or cyclic active methylene compounds containing heteroatom such as (2-thio)barbituric acid, Meldrum's acid using ionic liquids as reaction medium.

在第二部分中我们研究了离子液体中开链活性亚甲基化合物、杂环类活性亚甲基化合物如(2-硫代)巴比妥酸、Meldrum's酸与芳香醛之间的Knoevenagel缩合反应。

In chapter four molecular modeling method is employed to comparatively study five S-allyl γ-hydroxy ketene dithioacetals reactions of Thio-Claisen rearrangement with and without zeolite catalysts.

第四章用分子模拟途径研究了在有、无分子筛催化条件下五种丙烯基羟基乙烯酮二硫代乙缩醛Thio-Claisen重排反应。

By using this methodology, alkenyl silanes which have useful applications from a synthetic point of view could be easily obtained.

藉由改变起始物硫缩醛的取代基，或是使用不同的格林那试剂，我们能利用此烯化反应得到在有机合成上有许多应用的有机矽化合物。

The condensation of 3 carbethoxy isoquinol 4 one with carbamidine, amidine, carbamide and sulfocarbamide gave isoquinolo pyrimidine derivatives, respectively and isoquinolo quinoline derivatives were synthesized by the reaction of o aminobenzaldehyde or o aminopiperonal with isoquinol 4 one.

报道了利用 3 乙氧甲酰基异喹啉 4 酮分别与胍、脒、脲及硫脲类化合物缩合反应合成异喹啉并嘧啶衍生物，邻氨基苯甲醛、邻氨基胡椒醛分别与异喹啉 4 酮反应合成异喹啉并喹啉化合物。6个新化合物的结构通过元素分析、红外光谱、核磁共振氢谱和质谱予以证

In the presence of suitable nickel catalyst and without the chelation effect of special designed dithioacetals, simple aliphatic dithioacetals could react with a series of Grignard reagents to give the corresponding olefinic products.

因此在适当的镍触媒存在下，脂肪族硫缩醛在不需要特别的螯合作用下，即可以与一系列的格林那试剂进行烯化反应。

The new olefination methods of alkyl substituted propargylic dithioacetals are described in this thesis.

中文摘要本篇论文围绕在烷基取代炔丙基硫缩醛的新型态烯化反应，可分为两部分进行探讨。

A range of oligoaryls having alternating para- or meta-benzene-furan rings is synthesized by rapid convergent/divergent method from the annlation of a propargylic dithioacetal and an aldehyde having a propargylic dithioacetal moiety as the substituent.

中文摘要结合分流法/汇集法，利用炔丙基硫缩酮单体和另一具有醛基的单体进行环化反应，可以迅速合成对位及间位取代苯环呋喃交错寡聚物。

The PrP of bastard halibut consists of 472 amino acid residues, weighing about 49.6kD. The deduced amino acid sequence is 71.9% similar to that of Japanese pufferfish and 66.4% similar to that of Atlantic salmon, and bears the structural signatures of PrPs including a signal sequence, tandem repeats, a hydrophobic region, two glycosylation sites, a disulphide bridge and a glycosyl phosphatidylinositol anchor site.

推测的牙鲆蛋白质感染因子蛋白由472个氨基酸组成，分子量约49.6kD，具有信号肽、短肽顺接重复、疏水区、糖基化位点、二硫键、糖基缩醛磷肌醇锚定位点等蛋白质感染因子蛋白特征结构域，与红鳍东方鲀和大西洋鲑蛋白质感染因子蛋白的相似性分别为71.9%和66.4%。

The intermediate 5-amino-1H-pyrazole-4-carboxylic acid ethyl ester prepared in the first part underwent successively hydrazinolysis, condensations with ketene dithioacetals and alkylations to give rise to the dipyrazolyhnethanes.

从第一部分中的中间体5-氨基-1H-吡唑-4-羧酸乙酯开始，经过肼解、与乙烯酮二硫代缩醛的缩合反应和烷基化反应，合成了二吡唑基甲酮类化合物。

If you are unfortunate enough to the lovelorn, please tell me, I will help you out, really, please contact me!

如果你不幸失恋了，请告诉我，我会帮助你摆脱困境，真的，请联系我啦！

China's plan to cut energy intensity by 20 percent and pollutant discharges by 10 percent between 2006 and 2010 is a case in point.

中国计划在2006年到2010间降低20%的能源强度和减少10%的主要污染物排放，就是一个这样的例子。